No I think the MAF failed from a little romp prior to the scan and the trims are off at very low throttle? Sometimes at cruise the A/F goes nuts lean (17+) and then rich but as any throttle is added they come back to Stoich.

See if I can find a scan...

 

hey bill can i call you??

 

hey hey hey... your describing me i am running logs on way to work... posting them here... then tweaking.... then logging in the way home.... then tweaking at home... next day repeat

 

Yes, of course.


OK I added a longer scan, I made a couple of partial throttle tire spinning hits and then cruised for a bit.

 

every truck i have ever seen with a tune throws the front wheel speed sensors, they are tripped when you do a burnout or when you scratch a shift, when your VSS exceeds the wheel speed sensors it figures they are malfunctioning but as long as your ABS works they will stay as immatures and wont trip the SES

 

DTC C0035 or C0040
Circuit Description
As the wheels spin, each wheel speed sensor produces an AC signal. The electronic brake control module (EBCM) uses the frequency of the AC signals to calculate each wheel speed.

DTC Descriptors
This diagnostic procedure supports the following DTCs:

• DTC C0035 Left Front Wheel Speed Sensor Circuit

• DTC C0040 Right Front Wheel Speed Sensor Circuit

Conditions for Running the DTC
• The ignition is ON.

• The vehicle speed is greater than 13 km/h (8 mph).

Conditions for Setting the DTC
Any of the following occurrences may cause the DTC to set.

• The EBCM detects an open or shorted wheel speed sensor circuit for 500 milliseconds.

• The EBCM detects the absence of a wheel speed sensor signal for 5 seconds. If more than one absent wheel speed sensor signal is detected, the condition must be present for 120 seconds to set DTCs.

• The EBCM detects an erratic wheel speed sensor signal for 200 milliseconds.

Action Taken When the DTC Sets
• The EBCM disables the ABS and may disable the dynamic rear proportion (DRP) if more than one wheel speed sensor DTC is set.

• The ABS indicator turns ON.

• The brake warning indicator may turn ON.

The actions above are maintained during subsequent ignition cycles until the EBCM completes a power up self-test. This test concludes when the vehicle achieves a speed greater than 13 km/h (8 mph) and the wheel speeds are verified by the EBCM.

Conditions for Clearing the DTC
The Conditions for Setting the DTC are no longer present and you use the scan tool Clear DTCs function.

Diagnostic Aids
Thoroughly inspect connections or circuitry that may cause an intermittent malfunction. Refer to Testing for Intermittent Conditions and Poor Connections , Connector Repairs , Testing for Electrical Intermittents and to Wiring Repairs in Wiring Systems.

If the customer's concern is that the ABS indicator is on only during humid conditions such as rain, snow or vehicle wash, thoroughly inspect the wheel speed sensor circuits for signs of water intrusion. Use the following procedure in order to help isolate the problem area:

Spray the suspected area with a 5 percent salt water solution.
Operate the vehicle at a speed greater than 13 km/h (8 mph) for at least 30 seconds.
Repair or replace the suspect harness if the DTC sets.

Step
Action
Values
Yes
No

Schematic Reference: ABS Schematics

1
Did you perform the Diagnostic System Check - Vehicle?
--
Go to Step 2
Go to Diagnostic System Check - Vehicle in Vehicle DTC Information

2
Use a scan tool in order to clear the DTCs.
Operate the vehicle at a speed greater than the specified value.
Does the DTC set?
13 km/h (8 mph)
Go to Step 3
Go to Diagnostic Aids

3
Turn OFF the ignition.
Raise and support the vehicle. Refer to Lifting and Jacking the Vehicle in General Information.
Disconnect the wheel speed sensor connector.
Use a DMM in order to measure the resistance across the wheel speed sensor.
Does the resistance measure within the specified range?
700-10,000 ohms
Go to Step 4
Go to Step 8

4
Slowly spin the wheel by hand.
Use a DMM in order to measure the A/C voltage across the wheel speed sensor as the wheel spins.
Does the A/C voltage measure greater than the specified value?
100 mV
Go to Step 5
Go to Step 8

5
Inspect for poor connections at the harness connector of the wheel speed sensor. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 6

6
Disconnect from the electronic brake control module (EBCM), the harness connector containing the wheel speed sensor circuits.
Test the wheel speed sensor circuits for the following:
- An open

- A short to ground

- A short to voltage

- Shorted together

Refer to Circuit Testing and to Wiring Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 7

7
Inspect for poor connections at the harness connector for the EBCM. Refer to Testing for Intermittent Conditions and Poor Connections and to Connector Repairs in Wiring Systems.

Did you find and correct the condition?
--
Go to Step 10
Go to Step 9

8
Replace the wheel speed sensor. Refer to Wheel Speed Sensor Replacement - Front .

Did you complete the replacement?
--
Go to Step 10
--

9
Replace the EBCM. Refer to Control Module References in Computer/Integrating Systems for replacement, setup and programming.

Did you complete the replacement?
--
Go to Step 10
--

10
Use the scan tool in order to clear the DTCs.
Operate the vehicle within the Conditions for Running the DTC as specified in the supporting text.
Does the DTC reset?
--
Go to Step 2
System OK



--------------------------------------------------------------------------------

 

Ok, so that's good to hear
Thanks Shannon, I'll talk to my friends at the dealership in the morning.

 

blah blah blah blah. LOL..just kidding.

Roger he's in closed loop. Unless rick has changed his o2 switching points he shoud recover stoich quickly. He also has his maf failing at a particular hertz, but it should not matter, he is closed loop. The pcm should always find stoich. I didn't look at the scans.

Shannon, I thought there was a bunch of years that had recalls and some bullentins about front VSS'. Mine did. I don't get those codes on spinning.

 

there was an issue with cleaning the sensors if you see thats part of the article